حَدَّثَنِي إِبْرَاهِيمُ بْنُ مُوسَى، أَخْبَرَنَا هِشَامٌ، عَنِ ابْنِ جُرَيْجٍ، وَأَخْبَرَنِي مُحَمَّدُ بْنُ عَبَّادِ بْنِ جَعْفَرٍ، أَنَّ ابْنَ عَبَّاسٍ، قَرَأَ ‏{‏أَلاَ إِنَّهُمْ تَثْنَوْنِي صُدُورُهُمْ‏}‏ قُلْتُ يَا أَبَا الْعَبَّاسِ مَا تَثْنَوْنِي صُدُورُهُمْ قَالَ كَانَ الرَّجُلُ يُجَامِعُ امْرَأَتَهُ فَيَسْتَحِي أَوْ يَتَخَلَّى فَيَسْتَحِي فَنَزَلَتْ ‏<a href="https://quran.com/11/5-5">{‏أَلاَ إِنَّهُمْ يَثْنُونَ صُدُورَهُمْ‏}</a>‏

باب ‏<a href="https://quran.com/11/5-5">{‏أَلاَ إِنَّهُمْ يَثْنُونَ صُدُورَهُمْ لِيَسْتَخْفُوا مِنْهُ أَلاَ حِينَ يَسْتَغْشُونَ ثِيَابَهُمْ يَعْلَمُ مَا يُسِرُّونَ وَمَا يُعْلِنُونَ إِنَّهُ عَلِيمٌ بِذَاتِ الصُّدُور‏}</a>‏

Narrated Muhammad bin `Abbas bin Ja`far:

Ibn `Abbas recited. "No doubt! They fold up their breasts." I said, "O Abu `Abbas! What is meant by 
"They fold up their breasts?" He said, "A man used to feel shy on having sexual relation with his wife 
or on answering the call of nature (in an open space) so this Verse was revealed:-- "No doubt! They 
fold up their breasts."

"No doubt! They did fold up their breasts, that they may hide from Him. Surely, even when they cover themselves with their garments, He knows what they conceal and what they reveal. Verily, He is the All-Knower of the (innermost secrets) of the breasts." (V.11:5)

Sahih al-Bukhari

حَدَّثَنَا الْحُمَيْدِيُّ، حَدَّثَنَا سُفْيَانُ، حَدَّثَنَا عَمْرٌو، قَالَ قَرَأَ ابْنُ عَبَّاسٍ ‏<a href="https://quran.com/11/5-5">{‏أَلاَ إِنَّهُمْ يَثْنُونَ صُدُورَهُمْ لِيَسْتَخْفُوا مِنْهُ أَلاَ حِينَ يَسْتَغْشُونَ ثِيَابَهُمْ‏}</a>‏ وَقَالَ غَيْرُهُ عَنِ ابْنِ عَبَّاسٍ ‏{‏يَسْتَغْشُونَ‏}‏ يُغَطُّونَ رُءُوسَهُمْ ‏<a href="https://quran.com/11/77-77">{‏سِيءَ بِهِمْ‏}</a>‏ سَاءَ ظَنُّهُ بِقَوْمِهِ‏.‏ ‏<a href="https://quran.com/11/77-77">{‏وَضَاقَ بِهِمْ‏}</a>‏ بِأَضْيَافِهِ ‏<a href="https://quran.com/11/81-81">{‏بِقِطْعٍ مِنَ اللَّيْلِ‏}</a>‏ بِسَوَادٍ‏.‏ وَقَالَ مُجَاهِدٌ ‏{‏أُنِيبُ‏}‏ أَرْجِعُ‏.‏

Narrated `Amr:

Ibn `Abbas recited:-- "No doubt! They fold up their breasts in order to hide from Him. Surely! Even 
when they cover themselves with their garments.." (11.5)